Ignacio "Nacho" Beristain is a Mexico City-based boxing trainer and manager, who is considered by many to be Mexico's top trainer. He currently is the trainer of the Marquez brothers; Juan Manuel and Rafael, who hold world titles at Featherweight and Bantamweight, respectively.

Beristain's boxers have acquired a reputation over time, for their technical skills in the ring. However, he has been criticized by boxing writers, such as Dan Rafael and Steve Kim, for his cautious handling of the Marquez brothers, and failing to get them signficant fights in recent years.